This invention is directed to applicators for liquids and liquid reservoir containers for such applicators. It is particularly but not exclusively concerned with applicators for applying surgical prep liquids to the skin.
The conventional preparation of a patient's skin for surgery includes an extended period of cleaning using soap or the like, followed by the application of an antiseptic or disinfectant solution.
The oldest—and still widespread—method of applying the disinfectant is by dipping a swab, sponge or pad, held in forceps, into a dish of liquid and wiping it over the skin. Spent swabs/pads are continually discarded and fresh ones taken. The disinfectant (“pre-prep solution”) is usually alcohol-based and may contain ingredients such as iodine that irritate or burn the skin. Moreover surgical prep is often done under severe time pressure and subject to safety and effectiveness there is every interest in doing it as quickly as possible.
Over the years many proposals have been made for hand-held applicator devices for applying surgical prep solution, incorporating an applicator head with a pad, sponge or other soft or deformable permeable element to be wiped across the skin, and a reservoir of the surgical prep solution—usually contained in a handle of the device—communicating with the applicator pad to feed solution. This can make the application more efficient by avoiding the repeated dipping and the discarding and replacement of spent swabs. By providing the solution in a sealed sterile vial, ampoule or cartridge, which can be opened inside the device by engaging it appropriately with an opening structure in the applicator body (e.g. a spike or cutter built into the applicator body to rupture a membrane or film closure on the front of the cartridge, or an oblique shoulder to break off the tip of a glass vial) operation of these devices can be neater and easier than swabs.
Surgical prep solutions are desirably coloured or dyed, to show where the solution has been applied. This presents a problem with pre-loaded containers for applicators, because usually the dye additive cannot be included in the solution pre-packaged in the container. Dye compounds have a tendency to interact chemically, degrading both themselves and the disinfectant over time. Moreover they may be unable to withstand the sterilisation conditions needed for the main disinfectant solution. So, dye must be provided separately in the applicator.
U.S. Pat. No. 7,241,065 uses a porous plug impregnated with dye and positioned in the applicator in front of the solution ampoule. Disinfectant solution from the ampoule is coloured as it flows through the plug on the way to the applicator pad. Another proposal provides a solid dye powder on the back of the applicator pad. These proposals may bring assembly problems, and the mixing of dye and disinfectant is likely to be non-uniform over the dispensing lifetime of the applicator.
The issue exists not only for dyes, since there may be other additives or components which could desirably be included in a liquid applied by an applicator using a pre-loaded liquid container, but which for various reasons, such as those mentioned above, cannot be pre-mixed in the pre-loaded liquid. This can apply to solid or liquid additives.
The present application presents new proposals or embodiments for applicators using pre-loaded liquid containers, and for new kinds of pre-loaded container for use with such applicators, addressing the above issues.